Notes: Finally, here it is: Erwin's Birthday Night Surprise. I hope you enjoy it!

Kink details and possible TW: This chapter contains some light dub con elements. This is purely within the role-play scenarios – the characters fully consent to everything and have a safe word. I'm not even sure it's enough to warrant being called dub con, but I prefer to be cautious with my warnings.

There's also small depictions of degradation and choking kinks. I consider the content fairly light, but I think it's best to give a heads up about it. If you want more specific details before reading, feel free to comment in the review box, and I'll answer any questions!

Previously: Erwin returned from the trade summit in Mitras. He and Levi discussed possibilities for a more long-term relationship with Armin. Ultimately, they don't think it could work without them becoming public about their own relationship. Which is something Levi refuses to do – the traditionalists already dislike Erwin, and would tear his reputation apart if any scandal came out. They agree to end things with Armin in the foreseeable future, but don't pick an exact date.

For Erwin's birthday, Levi and Armin organise a cosy party. They also have another surprise in store for their Commander…

Chapter 21: Birthday Surprises

Erwin

As instructed, Erwin changed into his training uniform after his shower.

It was a pain having to don the straps of the ODM gear so late in the day. But Armin had made the request so enthusiastically, how could he refuse him?

Once dressed, he left his bedroom and walked down the hall to his quarter's private study room. Levi and Armin's hushed voices drifted towards him from the sitting room.

Are they still discussing their last minute plans? Exactly how complicated is this role-play?

Sitting down at his desk, he pulled a stack of papers towards him. 'Pretend to be doing paperwork when we come in,' Levi had ordered him earlier. But maybe he could actually squeeze in a few minutes of work before the other men arrived…

Concentration proved difficult, of course. Thoughts of what Levi and Armin were planning kept invading his mind.

"We'll take care of everything. You just need to relax and enjoy it," Levi had assured him.

Will they include any of the suggestions I gave to Levi last night? he wondered.

Excitement thrummed in his chest imagining what might be in store. But his anticipation soured into dread as an unwelcome memory jabbed at him.

Earlier today, he'd received a letter from the Military Relations Commission – a government body which promoted the welfare of soldiers, and investigated military misconduct. The MRC had only been established after the governmental shake-up a few years ago. Since assuming the role of Commander, Erwin had attended a few of their information meetings with other military leaders.

Their recent letter was strangely vague – it simply stated that that two representatives from the Commission would be visiting the Survey Corps headquarters next Monday, and they wished to speak with him. No more information was given about the reason for the visit.

Dark possibilities had floated around his mind all day. Is there an issue with my role as Commander? Or is this something to do with my relationship with Levi? Have they heard rumours about us, and are now investigating it?

A stray remark from the summit in Mitras came forcefully to mind. Alastair Forster, one of the more outspoken traditionalists, had sneeringly asked Erwin whether Humanity's Strongest Soldier had come with him to the summit, seeing how they were such good friends.

Erwin had chosen to ignore the insinuation. Rising to barbs like that would only provoke more suspicion. He didn't even tell Levi about the incident.

But had he seriously underestimated the situation? Were the traditionalists spreading rumours, hoping to weaken his position as a military Commander?

It wasn't officially forbidden for soldiers and officers to have relations with each other. At the same time, it wasn't exactly encouraged either. And the revelation that he was in a same-sex relationship would cause at least a minor scandal.

Then again, it might not be so bad. A few months ago, Vivian Prendergast in the Military Police announced she was in a relationship with a fellow female soldier. There had been many disparaging comments thrown around, yes. The traditionalists had used it as an example of how Paradis was being corrupted by the influence of foreign nations. But Erwin had been pleasantly surprised to hear a lot of support for her too. Ultimately she'd been allowed to keep her position as Lieutenant.

All day long, he'd gone back and forth on whether to tell Levi about the letter from the Commission. In the end he decide not to worry him about it right now. He was so excited for tonight, after all.

Erwin rubbed at his temples. The edge of a migraine was prickling under his skin, one he hadn't fully shaken since receiving that ominous letter earlier today. Gritting his teeth, he focussed his attention on appreciating how much effort his partner and Armin had put into tonight.

The cosy party earlier – the sumptuous cake, Armin's creative decorations, and both men's thoughtful gifts – were more than enough for Erwin. And yet they still had another present waiting for him tonight.

How far would they go in 'taking charge' of him? Would Armin be willing to try any of the suggestions he'd given to Levi? He didn't want him doing anything he was uncomfortable with, after all.

Then again, lately the young man was very upfront about what he did and didn't want to do. Take his anxiety over anal sex, for instance. He'd firmly told them he wouldn't be ready to try it again for a while. Possibly never at all. Levi and Erwin had respected this, and agreed to leave it to him to bring up the topic if he ever changed his mind. And in terms of tonight, they all had the right to use the safe word 'red' if any of them felt uncomfortable.

From the sitting room, Armin's muffled laughter broke the silence. Erwin's heart skipped at the noise.

Perhaps I should stop worrying. By the sounds of it, he seems to be eager about tonight, too.

When his attempt to get some work done failed, he glanced around the room. His lips quirked as he noticed a towel folded on his filing cabinet. No doubt Levi had left it there earlier in preparation for their upcoming activities.

Walls, I hope they hurry up! I need a distraction tonight…

His heart leapt as footsteps approached in the hall outside. Knowing Levi wanted him to play the role of Commander, he picked up a report when the door opened. It took all his willpower to focus on the words in front of him. From the edge of his vision, the two men entered the room.

"I'll be with you in a moment," Erwin said, pretending to scan the rest of the page. In reality, he used the time to regulate his erratic breathing.

After a few seconds he asked, "Now, what can I do for you gentlemen?" and lifted his gaze.

His brain froze as he processed the strange sight before him.

Levi and Armin stood inside the doorway. But there was something distinctly wrong about them. After a few seconds, Erwin's baffled mind registered exactly what this was. The report slipped out of his lax hands.

Levi was wearing Armin's favourite blue jacket, the very same one the librarian had worn earlier at the party. His fringe was brushed out to cover his forehead similarly to the other man's too. Most strikingly, on his nose perched a pair of spectacles – which looked suspiciously similar to the ones Erwin had seen Armin wearing while working at the library.

Meanwhile, Armin was dressed in Levi's black suit jacket and dark trousers, with a cravat secured at his throat. His fringe was also rearranged from its usual style, and now hung ruggedly over his eyes.

They've dressed up as each other?!

Armin glanced at Levi beside him. Levi leaned in to murmur something in his ear, and Armin nodded. He crossed his arms and stepped forward.

"Sorry to interrupt you, Commander," Armin said. His tone, marked with a quiver, harnessed more certainty the longer he spoke. "But Arlert and I agree that you've been working too hard lately. So we thought we'd show you our appreciation."

Levi nodded, eyes fixed on the wooden floor. "Yeah, you deserve a reward for all your hard work." He spoke in the same shy, breathy voice he'd previously used when pretending to be Armin in their bedroom games.

So they're not just dressed as each other; they're impersonating one another too!

Armin pushed the door closed behind him. "You spend all day being in charge and giving orders… You must be sick of all that responsibility. Why not let us take some pressure off you? Let someone else be in charge for a change. Before you refuse – I should warn you that we won't take no for an answer."

A bubble of laughter threatened to escape Erwin's lips. He held it back. They've clearly put a lot of thought into this charade, I won't spoil it for them!

It seemed they were gearing towards a more forceful approach to this seduction scenario; something he himself had suggested to Levi for tonight. Heat prickled along his skin at the fantasy of being 'overpowered' by these two men. How far would Armin be able comfortable with the taking the role?

Struggling to keep a straight face and play the part of the calm, confident Commander, he replied, "I'm always happy to make time for my two favourite soldiers. But I'm not convinced that what you're suggesting is a good idea." He put down the pen he'd been twisting in his hand, and met their gazes levelly.

Armin took a hesitant step forward. Then he froze, chewing his lip and toying with the sleeve of his jacket. (Or rather, Levi's jacket.)

Erwin shifted tactics to try coaxing Armin out of his stage fright. He smirked, letting his gaze slide up and down both men. "As attractive as you both are, we could all get into trouble if word about this gets out. I don't know if I'm willing to take that risk."

Levi stepped up behind Armin, placing his hand on the younger man's back, but keeping his gaze on Erwin. "Oh, we'll make it worth your while Commander." He leaned into Armin's ear and whispered audibly, "Do you want to start, Captain? Or should I?" He murmured something else which Erwin couldn't catch, but the tone was gentle.

Whatever it was, it seemed to bolster Armin's resolve.

"No brat, I'll go first. But you can help me."

Armin took a breath before strolling around the desk towards Erwin. He raked his eyes up and down his superior's body, assessing every inch of the uniform clinging to his muscular body.

The reason for their request for him to wear his training uniform became clear. It helps set up the power dynamic – having me dressed as a soldier, while they're dressed more formally. I might still be the Commander in this scenario, but they're the ones with the power.

Armin's confidence wavered again as he stepped right up to Erwin's chair behind his desk. When Erwin caught his eye, he glanced away, fingers toying with the buttons on his (or rather, Levi's) jacket.

Doesn't he know how hot he looks dressed like that? I better give him a little encouragement…

Reaching out to grip Armin's wrist, he said, "Captain, we really shouldn't do this." He did his best to look conflicted, letting his own eyes roam over the other man's body.

This did the trick in snapping Armin back into his role. He curved his lips into a devastating smile, making heat pool in Erwin's groin.

"Tsk Commander. You're not the one charge right now…"

The 'Captain' leaned over and set his hands on the armrests either side of him. He swooped down for a hard kiss. Erwin could feel a slight tremble from him at first, but it swiftly disappeared after Erwin moaned into the kiss, and opened his mouth for the other man to plunder.

Armin's hands wandered possessively over Erwin's shoulders and arms, squeezing the taut muscles approvingly.

"Fuck, you're so big Commander…" Armin exclaimed, trailing off suggestively. He smirked at the bulge in Erwin's trousers. Then trailed his fingers along his upper thigh. "You can't tell me you don't enjoy this now."

Disappointment coursed through Erwin as Armin ignored his cock, and matter-of-factly began unbuttoning his shirt instead. He tossed his head towards Levi, who was hovering by the wall watching the proceedings with rapt attention. "Brat! Get over here and help," Armin demanded.

Maintaining his wide-eyed, curious expression, Levi walked over. He perched on the armrest and smiled demurely at Erwin.

"We're going to make you feel so good, Commander," he whispered. He traced his fingertips in reverence over Erwin's newly bared chest.

Erwin reciprocated the gesture and ran his hand down Levi's chest, enjoying the sensation of hard muscles under his shirt. The fact Levi was wearing Armin's clothes made his pulse beat all the faster.

But this displeased the Captain, and Armin swatted Erwin's hand away from Levi. "No Commander. We're in charge tonight, remember? You're not allowed to touch us until we say so."

Erwin didn't need to feign the frustration in his reply. "What am I allowed to do then, Captain?"

"Just sit back and let us reward you for being such a good Commander."

Erwin's annoyance was swiftly replaced by hot desire as Armin knelt down in front of him. He took his sweet time adjusting his position on his knees, probably to draw out the anticipation. And it was working. Erwin clenched and unclenched his fists since he wasn't allowed to touch either of the men.

When Armin finally opened his trousers and pulled out his cock, Erwin gritted his teeth against the overwhelming self-consciousness that swept over him. Both men were staring at it – Armin with a sly smirk, and Levi with open fascination.

"Fuck. Well we shouldn't be surprised that you're massive. I just wonder how I'll fit this in my mouth…"

Armin's hand encircled his girth, and began stroking it at a leisurely pace, coaxing it out to its full size. The little rogue maintained eye contact with Erwin, as if seeking a reaction. Feeling acutely exposed, Erwin steeled his will against making any embarrassing noises of pleasure. He focussed all his attention on regulating his ragged breath.

Armin circled a thumb over his tip, uttering some lewd remark about how wet he was already. But Erwin didn't catch the words – he was too busy noticing how Armin kept flicking his gaze to Levi. Was he checking if the man was ok with everything?

Erwin turned his own head to face his partner. Levi was still perched on the armrest, with his hand resting on Erwin's shoulder. His gaze was fixed on Armin like he was a slice of that delicious birthday cake they'd all shared earlier. Clearly, he wasn't faking his enthusiasm for this role-play. When he caught Erwin looking at him, he bit his lip in an imitation of Armin, and one corner of his mouth tilted upward.

Between Erwin's legs, the Captain began licking slow, lazy stripes from the base to the tip. The flame burning in Erwin's stomach was threatening to consume him if Armin dragged this out any longer.

"Fuck it, Armin- I mean, Captain!" he growled. "Stop teasing."

The smirk on Armin's face was so wicked, Erwin genuinely wondered if the man had gotten a personality transplant. But the knowledge that the sweet, 'innocent' little librarian got off on torturing him sent a fresh spark of arousal through his veins.

The Captain ceased his licking, and gripped the base of Erwin's cock. Then Armin's blissfully hot mouth wrapped around the head of his erection. Erwin couldn't hold back a low moan. Watching Armin performing this task, whether for himself or for Levi, was always a satisfying sight.

However, this time was different.

For the first time since he'd become involved with them, Armin dominated the proceedings. Erwin was under no illusion as to who held the power. He might still be the Commander, but Armin was the one truly in command of the situation.

Levi crooned praise and ruffled Armin's hair. "You look so good sucking off your Commander, Captain."

Somehow in the fog of Erwin's thoughts, he appreciated his partner's kind encouragement. Not to mention the evident enjoyment dripping from his words.

Armin sank down further to engulf about half of Erwin's length. He soon established a rhythm – sliding his mouth up and down at an unhurried pace, while his hand matched the motion at the base of Erwin's cock. As much as Erwin wanted to watch the show, the intense pleasure forced him to squeeze his eyes shut. He ground his teeth; some innate impulse demanded that he retain his dignity and not verbalise his enjoyment. Who knew what sort of mortifying sound he'd make if he opened his mouth? Instead he dug his fingers deep into the fabric of the armrests on his chair, resisting the urge to buck his hips towards Armin.

The Captain emitted a low noise in his throat. Erwin's eyes snapped open to check on him. The man's eyelids were shut and glistening, his cheeks rosy from exertion. Without thinking, Erwin reached out to convey his appreciation by stroking Armin's soft hair. But Levi snatched the offending hand away and pinned it to the armrest.

Armin pulled off Erwin's cock with a wet sound. "You're not allowed touch us Commander. What part of that don't you understand?" His tone was as soft as the pages of a new book, and just as sharply edged. "Do you promise to do what you're told?"

"Fine! I'll do what you say," Erwin said breathlessly.

"You're such a good boy for us," Levi purred, patting his head.

So much for maintaining my dignity…

Still, the prospect of both men ignoring his superior rank and pleasuring him on their terms was insanely arousing.

Any tinge of shame evaporated as Armin sank his mouth back over Erwin's cock. A deep sigh escaped the Commander's lips, heightening to a groan when the wet, tight heat engulfed even more of his length. Armin's mouth strained to accommodate him, and this time he fixed his glittering blue gaze firmly on Erwin's.

He's never given oral like this before. Did Levi teach him a few things?!

Armin tried sinking down even further, but made a gagging sound. Levi lunged forward to help him.

"Take it easy, don't hurt yourself." He cupped the back of Armin's head while the man pulled off and regained his breath.

"Do you want to stop?" Erwin wiped the moisture on the man's chin away with the back of his hand.

Armin cleared his throat. "No, it's fine. I can keep going." He looked back up, the powerful façade cracking as he ran a nervous hand through his hair. "Is this all ok? If it's too much I can do something else-"

"No, you're doing great! Both of you."

Erwin swept his gaze over them. Levi knelt beside Armin, rubbing his back. He murmured a teasing remark under his breath and the librarian broke into a smile.

They're so good together. Erwin's chest squeezed with fondness, tinged with regret. I wish we didn't have to end things...

Getting back into his role as Armin, Levi asked, "Captain, can I have a turn with the Commander? It's my turn to play with that massive dick."

This statement definitely wasn't very Armin-like. But a sex-starved Armin was an interesting portrayal all the same, and Erwin wasn't going to complain.

Armin, clearly seeing Levi wanted some time with his partner, quickly agreed. He stood up to allow Levi to move between Erwin's legs, and leaned against the desk to watch with crossed arms.

Levi took over the task, playing innocent at first and teasing Erwin some more. His tongue flicked over the sensitive skin at the head of his erection, delicately probing the leaking slit. The bastard knew what he was doing. Soon Erwin was panting again, too wrapped up in the exquisite sensations to care what noises fell from his lips.

"Tell us when you're close, Commander," Armin instructed.

Then he claimed Erwin's mouth in a demanding kiss. He swirled his tongue around his mouth like he owned it, before biting down gently on his lower lip.

It wasn't long before Erwin's pleasure built to a soaring height, and he was indeed about to finish.

"I'm close," he panted.

"Stop, Arlert," Armin commanded. Almost immediately, Levi pulled his mouth off Erwin's cock.

Those bastards! Erwin's mind roared. But it was his own fault. Edging was another thing he'd told Levi he was up for doing tonight. And now he was getting exactly what he'd asked for.

Armin pulled Levi to his feet. He pushed him back against Erwin's desk, so he was half sitting on it. Tossing his head back to Erwin, he ordered, "Keep your hands on the armrests, Commander."

Then he focussed his attention back on Levi, who was adjusting his glasses, and looked the picture of innocence in the blue jacket. The Captain grabbed a fistful of the librarian's shirt, tugging him closer. He kissed him. His hands slid possessively over Levi's compact muscular body, mapping the man out like a precious possession. When their lips broke apart, Armin sank his teeth into the skin where Levi's shoulder met his neck.

"Fuck," Levi hissed in rebuke. But the bulge in his trousers attested to his enjoyment of the proceedings.

Erwin too was savouring the show. He'd never seen them kiss like this before. And the thought of those mouths pressed together, which had so recently been lavishing on his cock…

Erwin's hands on the armrests clenched into fists, aching to wrap around his erection. The prospect of Armin's angry reaction was sorely tempting. But he wasn't sure what the punishment would be. And there was a certain thrill to obeying the young man's orders.

Armin broke contact with Levi, who now looked thoroughly debauched – his hair a mess, glasses misted up, and open shirt revealing a series of red marks from Armin's teeth.

"Alright Commander, I think it's your turn again."

Armin arranged himself back between Erwin's legs, this time hooking his fingers under the tight straps of the ODM gear around his thighs. He wasted no time in getting back to work. He set a steady pace, taking a manageable portion into his mouth. One hand stroked the base in time to the movement of his mouth, while the other toyed with the ODM straps.

Erwin's pleasure swelled with a thunderous gravity, luring him higher and higher towards the peak.

"I'm close," he warned.

A flutter of panic went through him when Armin didn't stop. Breaking the role-play charade, he said, "You need to pull off Armin."

Suddenly he remembered a conversation with Levi a few days ago. Originally, Levi had been the one to impose a condition of 'no swallowing' during oral sex while they were with Armin. But he said he'd reconsidered it, and asked if Erwin was happy to relax the rule too.

And I was. But I'd assumed I was being given permission to do it for Armin, not the other way around!

"Are you ok with this, Erv?"

Levi squeezed Erwin's shoulder. His other hand clasped the back of Armin's head in an encouraging, but not forceful, gesture.

Concerns flitted across Erwin's mind – what if Armin felt pressured to do this? Or that it made Levi uncomfortable? But judging by the men's enthusiasm for the performance, he had no reason to believe these were actual issues.

He nodded in response to his partner's request.

Levi slipped straight back into his role, urging Armin on. "You're doing such a good job, Captain. It won't take long to finish our Commander off."

These words proved accurate. The sight of Armin bobbing so lewdly up and down on his cock was something straight out of his guilty fantasies. He squeezed his eyes shut as his orgasm crashed over him in waves of intense, scalding pleasure…

Armin seemed to be doing fine at first. But after a few seconds, the heat around his cock vanished as the man pulled off him.

Erwin's perception blurred in his heightened state of sensitivity. He heard a choking sound and then coughing. Eyes snapping open in hazy concern, he was relieved to see Levi already rushing forward, grabbing the towel and holding it up to Armin's dripping mouth.

Levi

Armin turned away from Erwin as he coughed, struggling to swallow. Fluid dripped down his front and spilled onto the wooden floor.

Levi snatched the towel he'd left on the filing cabinet earlier. Returning to Armin, he wiped the man's mouth and patted at the wet mess on his shirt.

Armin wriggled out of Levi's dark jacket as if afraid to get spit on it. "I'm s-sorry," he spluttered, before covering his mouth and coughing again.

There wasn't much more that could be done for the shirt. So Levi used the towel to mop up the small mess on the floor.

"Don't worry about it. Do you want some water?"

"No. I'm ok." Armin got unsteadily to his feet, gripping the edge of the desk. Leaning against it, he fumbled at the cravat at his neck. His mouth quivered like he was on the verge of tears.

"I'm so sorry Levi, I got this dirty too-"

"How many times do I have to say, 'don't worry about it,' before you'll believe me?"

Levi helped him unknot the cravat and then placed it on the desk. Everything could be washed later, there was no harm done.

Besides, it's a small price to pay for giving Erwin what looked to be one hell of an orgasm. And I certainly enjoyed the show too…

He patted the young man's back. "You don't think I've gotten Erwin's cum on my clothes before?"

Armin, having already abandoned his façade as the stony Captain, grinned sheepishly. He raised his sleeve to wipe at his eyes, but froze, as if recalling who's shirt he was wearing. Levi dutifully fetched him a handkerchief to use instead.

Erwin watched the men in silence as he refastened his trousers. Then he stood up on shaky legs.

"That - that was incredible. I really appreciate all the effort you put into it." He threw his arms around both of them. "Armin, are you feeling ok?"

"Um, yeah," Armin winced. "I just wish I hadn't spoiled things at the end. Maybe it wasn't a good time to try swallowing for the first time."

Erwin sat back on the chair, pulling both men down to perch either side of him on the armrests. He hooked an arm around each of their waists. "You didn't spoil anything, you were wonderful! I can't tell you how hot the whole 'bossy Captain act' was," he murmured, nuzzling his neck.

Armin's face blazed with self-satisfied embarrassment.

"So you enjoyed our little performance, Commander?" Levi's lips curled.

"Yes," Erwin chuckled. "You two are quite the team."

"Some of the acting was a bit shaky, but we didn't do too badly."

"Those glasses really suit you," Erwin smirked.

Fuck, I totally forgot I was wearing them! Perhaps Armin will let me borrow them another time…

He removed the glasses and folded them on the desk, shrugging off his embarrassment. "Well, I figured they'd help me sell the hot librarian look. It works for Armin, after all."

"I wear those for my eyesight!" Armin protested.

"Of course you do." Erwin shared a sceptical glance with Levi.

Which earned him a poke in the ribs from the disgruntled librarian.

"Ouch, I'm only teasing!" Erwin rubbed his side.

"You better behave Commander, or we'll punish you." Armin's tone was serious, but his cheeks puffed out like he was restraining laughter.

"I'll be good," Erwin promised. His grip on Levi's waist tightened. "Thank you both for the amazing birthday gift."

Levi shot Armin a meaningful look. "Oh, we're not done yet, Commander."

Erwin's initial thrilled expression quickly sobered. "You don't need to do anything else-"

"Hey, we're in charge tonight, remember?" Armin cut in.

"So birthday boy, what do you want to happen next?" Levi traced a fingertip over Erwin's cheekbone. "It's completely up to you."

It was always very satisfying to see the Commander flustered. Knowing what he – and Armin – could do to him was extremely empowering. They really did make a great team.

Erwin opened and closed his mouth, as if trying to verbalise his thoughts. Levi took pity on the man.

"Should we move into the bedroom?"

Erwin's mouth quirked with the ghost of a smile. "Would you be alright if we stayed in here?"

Levi snorted. I guess he misses those times we used to fool around in his office. At least this study is a lot safer.

When he and Armin agreed to Erwin's request, he added, "And… could you both keep acting dominant? But this time as yourselves, and not each other?"

Armin shifted in his seat on the armrest. "It's easiest for me to play that sort of role when I'm pretending to be someone else. I'm not sure I can do it otherwise."

"Could you give it a go? I think you'd be really good at it." Erwin's words dripped with honey.

"I also approve of seeing more assertive Armin," Levi added. "But don't get us wrong - we like cinnamon roll Armin too."

After much glaring and dramatic sighing, Armin agreed to give it a go.

As much as their banter lifted his heart, Levi was all too aware that this was probably one of their last nights with Armin. He wanted Erwin to make the most of it.

"You two play around first, I'll watch."

Both Erwin and Armin looked surprised. "Are you sure?" His partner asked.

"Armin deserves some attention after his hard work earlier," Levi shrugged. "Besides, that way you can save the best for last."

Erwin must have given this particular role-play scenario a lot of prior thought. Because he knew exactly what he wanted from Armin.

Levi hung back against the far wall, stifling his laughter at the over-the-top performance. But it was hard improvising like this with no preparation. They were both giving it their best shot.

Levi had given Armin his blue jacket and glasses back, as well as a clean shirt to wear. After hashing out the role-play details, the man wasted no time in throwing himself into the part. Snatching a random book from the shelf, he brandished it at Erwin, who was seated in his chair.

"This is the third time this month you've damaged a library book, Commander! What have you got to say for yourself?"

"I'm sorry, Librarian Arlert."

Armin slammed the book on the desk. "Your apologies mean nothing to me anymore, Mr Smith. I have no choice but to ban you from the library."

"Please… isn't there something I can do to change your mind? I'll do anything." Erwin's features were full of remorse. But his last words slipped into a silky, suggestive tone.

Armin crossed his arms, tilting his head as if in thought.

"Hmm. Perhaps there is something you could do to gain my forgiveness…"

As hilarious as the whole scenario was, Levi admired Armin's efforts at playing an unfamiliar role. He really does have a knack for this dominance thing once he gets going.

Levi recalled the man pushing him against the desk earlier. They'd agreed beforehand to put on a bit of a show for Erwin. But Levi hadn't anticipated to be quite so ravished by Armin. His fingers traced the sensitive spot on his neck where the man had bitten him. Being marked like that was such a primal, possessive gesture. It wasn't right to allow Armin to do it to him.

And yet, Levi's cock twitched as he imagined submitting to the man all over again.

But not tonight. We're focussing on Erwin, after all…

The librarian wasted no time in showing the naughty Commander what he wanted. Armin crawled onto Erwin's lap, straddling his large thighs with his own legs.

Erwin's eyes were huge with shock as the smaller man sat on him. Levi covered his mouth to smother a snort of laughter at the pretence. He knew Erwin was loving every fucking minute of this. Being coerced into sex was a fantasy he indulged in from time to time with Levi.

Armin began by ordering the Commander not to touch him, and to keep his hands on the armrests. Then he wasted no time in opening both of their trousers. With one hand grasping the ODM gear strap at Erwin's shoulder, the other frantically gripped and stroked their hard cocks together.

It's a pity Armin's not ready for anal sex yet. I'd enjoy watching him ride Erwin like this, completely in charge…

"Fuck, Arlert!" Erwin pleaded.

"What do you want, Commander?"

Erwin had made his request earlier when they discussed the role-play. But Armin seemed intent on drawing the words out of him again.

"I want… I want you to come on me… please."

"You're so filthy minded, Commander. But I'll give you what you want."

"Can you hold my throat too?" Erwin's words tumbled out.

They hadn't agreed on that in advance. Armin's bossy librarian façade faltered.

"You mean like – like choking you? I don't know if I'm comfortable doing that…"

"I'll do it." Levi moved away from the shadowy corner of the room, towards the men. "If you don't mind me getting involved?"

A languid smile graced Armin's lips. "Yes, I could use your assistance, Captain."

"Do you promise to be a good boy for us, Commander?" Levi asked his partner.

"Yes," Erwin hissed.

"Yes what…?"

"Yes, Captain."

Levi trailed his fingertips over Erwin's bare neck, eliciting a shiver from him. But he wouldn't give him what he wanted just yet.

Armin was busy pleasuring himself and Erwin. Having grown tired of stroking them both at the same time with one hand, he now occupied each of his hands to the task of pumping a cock. Levi rubbed slow, encouraging circles over the librarian's back, silently conveying his approval.

A low whine broke from Armin, indicating he was close. As per earlier instruction, he stopped touching Erwin and focussed on chasing his own pleasure instead. Levi would have the gratification of getting his partner off after Armin had his fun. The three of them had agreed it was the best way to end the night's activities.

Levi reached up to grip Erwin's throat. He flexed his fingers lightly – not enough to impede the man's breathing, but simply a show of dominance.

Armin made the most sinful noises. His free hand dug into the Commander's shoulder as he came, spilling himself all over the man's chest.

Levi clenched his teeth at the mess. Having someone shoot cum all over him certainly wasn't his own idea of a good time. But a visceral thrill shot through him at his partner's enjoyment of the degrading act.

He tightened his grip on Erwin's throat. "You're such a dirty slut, Commander," he whispered.

Erwin's moan reverberated under his fingers. Moments later, it became painfully clear that Levi had miscalculated just how turned on the man was. Specks of his partner's hot cum splattered Levi's hand around his throat.

How the fuck did he come untouched? I can't remember the last time that's happened…

"I'm sorry," Erwin panted. "I didn't realise how close I was." He closed his eyes, still breathing heavily.

He'd already come twice in less than an hour – how long would it take for him to be ready to go again? Pushing down both his disappointment and squeamishness over the mess, Levi tried to make light of the situation.

"Well, with Arlert moaning like a goddamn whore, I'm not surprised you came. I almost did too."

He helped Armin off Erwin's lap, handing him the towel to wipe himself off (although most of the mess had ended up on Erwin). Both men were quiet as they tidied up.

Shit. Do they think I blame them for what happened?

Levi softened his tone. "Look, you both enjoyed yourselves, that's all that matters."

"Give me a few minutes and we can continue on as we planned," Erwin said hurriedly.

He's fucking exhausted! Is he really capable of going a third time? I don't exactly want to ask him that in front of Armin…

"It's been a long day." Levi leaned in to brush Erwin's sweaty hair off his forehead. "I don't mind if you want to leave it at that."

Erwin didn't protest immediately. Which confirmed to Levi just how tired the man was.

"Are you sure? You didn't get much out of tonight, it's not really fair to-"

"Erwin. All I wanted for tonight was for you to enjoy yourself. And did you?"

"Yeah, it was amazing, but-"

"Then I'm satisfied." Levi gave him a peck on the cheek. "Besides, Armin put on quite the show. He did a great job of looking after you."

Armin stared at them, twisting the towel between his hands. "Levi? Do you want me to… you know, help you out?"

His heart warmed at the offer. Clearly Armin understood the awkward situation. Possibly even felt bad that he'd spent more time with the Commander tonight than his actual partner had.

"Feel free to continue the little display you two showed me earlier," Erwin grinned.

Levi wanted nothing more than for Armin to push him against the desk again. To feel his hands roam all over him, his mouth on his neck. His desire roared at the thoughts of being utterly devoured by the man.

Then guilt shot through him like a blast from a thunder spear. Perhaps it wasn't a good idea right now. Nevermind the fact he was exhausted too – all this role-playing was a mental challenge.

"I'm happy to end things here," he declared. "Do you still want to have that bath, Erv?"

Spending some time alone with Erwin would surely appease his guilt over the strength of his need for Armin…

Armin

After showering in the en-suite bathroom, Armin went into the bedroom. He pulled out pyjama bottoms and a loose top from Levi's drawer. It would make more sense for him to simply leave a spare set of pyjamas here. But Levi always insisted it was fine for him to borrow his clothes.

Perhaps leaving my possessions here would feel like I'm encroaching on their space?

He hoped the other men were enjoying their bath together. By the sounds of it, Erwin was so busy lately that they hardly ever got to do this anymore. They'd assured Armin he was free to hang around for their usual routine of cuddling afterwards.

Armin sat on the bed, fiddling with the fancy bedspread. Erwin really seemed to have enjoyed himself tonight, despite Armin messing up the end of the oral session. And the unfortunate conclusion to the night's activities.

I wish Levi and Erwin could have finished things off together like we'd planned! I know it's not my fault, but it doesn't seem fair that I spent more time with Erwin than he did tonight.

His stomach rumbled. How long had it been since they'd eaten that birthday cake? At least two hours, maybe more. Levi and Erwin were probably hungry too…

When the men came out of their bath twenty minutes later, they headed into the bedroom. There they found the young librarian lying in the centre of Erwin's bed, reading a book. A tray rested on one of the bedside cabinets, laden with a tea set, and three slices of Erwin's birthday cake on plates.

"Armin Arlert, what's the meaning of this?! You better not be planning on eating that cake in here."

Levi's explosion might have been more frightening if the man was fully dressed, instead of wrapped in a fluffy bathrobe.

"Oh, I just thought since it was a special occasion, maybe it was ok?" Armin closed the book, trying not to smirk.

Erwin's gaze swivelled from Armin, to the cake, to his partner. "Please can we eat in here Levi? Just this once?"

The Captain hissed out a noise of frustration. Without replying, he picked up the teapot and began pouring out tea into the cups.

"This was really thoughtful of you," Erwin said, squeezing Armin's arm.

The three of them settled into bed, sitting upright against the headboard so they could drink and eat comfortably.

"You brats better not get crumbs on the sheets," Levi muttered.

"Why, will you punish us?" Armin hid his smile by taking a sip of tea.

"Watch it, little librarian, or I'll be holding you down next time."

Armin's face grew hot. "Actually, that reminds me… when can try out that fantasy I told you about a few weeks ago?"

Erwin and Levi shared an indecipherable look.

"Perhaps we can all discuss it some evening next week?" Erwin suggested. His tone sounded a little hesitant. Was it just because he was tired?

After finishing their post-midnight snack, they cuddled under the duvet with Armin in the middle. Erwin mumbled his thanks to both men for a wonderful birthday. A few minutes later, his breathing grew heavier as exhaustion finally overwhelmed him.

Time for me to go soon, Armin decided. But first he wanted to settle something with the Captain.

"Levi, I'm sorry things didn't go according to plan earlier."

The man shifted so he was facing him. "These things happen, don't worry about it." His gruff tone was offset by reassuring arms winding around Armin's waist.

Armin closed his eyes, head resting against Levi's warm chest. How could someone with such an icy temperament be so irresistible? He was like the bitterest blend of tea, sweetened with a dash of honey.

"I should leave," Armin mumbled through a yawn. "You'll probably murder me if I fall asleep here."

"Tsk, stop being dramatic." Levi's voice was soft, like the brush of a butterfly's wings. "You can stay if you like. Erwin won't mind."

Armin's foggy brain tried to decipher these words. "Don't you mind?"

"No. It's really late; it's not fair to kick you out now."

"Are you sure? I don't want to cause any trouble-"

"Arlert. It's up to you - stay or leave. I'm too goddamn exhausted to argue over it."

"You're so grumpy when you're tired," Armin muttered, settling back against Levi's chest.

A feeble part of his mind protested. There was a good reason he never stayed the night with these men. The rule might have been created by the couple, but it was for his own protection too.

It's fine. It'll only be this one time, he promised himself as he sank into sleep.

Just this once…

Notes: I hope the role-play at the start with Armin & Levi acting like each other wasn't too confusing to read! I've wanted to show a scene like this for ages, and this was the best place to do it. The 'bossy librarian and naughty Commander' role-play idea was suggested by my friend Maia. I'm sorry if everything ended up more hilarious than sexy lol

I decided to focus on Armin/Erwin for this chapter, because sometimes it feels like Rivarmin and Eruri overshadow this ship. And while it was supposed to be a 'fantasy' night, I always enjoy showing sex going wrong. It leads to some nice characters interactions!

So what did you think of this chapter? How are you feeling about the future of the threesome? Something big is happening next time… you may have already noticed the hints. I'd love to hear your thoughts, and thanks for reading!